The invention relates to an apparatus for removing a surface layer including the skin from fish fillets, comprising a feeding device for feeding the fish fillets lying skin side down tail end first in transport direction T in the region of a separating arrangement, a dispatching device for dispatching the fish fillets freed from the surface layer and the separating arrangement, the separating arrangement comprising a rotationally driven driver roller arranged downstream of the feeding device and upstream of the dispatching device in the transport direction T of the fish fillets, said driver roller having a drive direction A synchronous with the transport direction T, a main blade arranged in the region of the driver roller for removing the surface layer and a pressing element active in the region of the main blade for pressing the fish fillets onto the textured conveying surface of the driver roller, wherein the main blade is arranged at a distance from the driver roller to form a cutting gap S and is designed to be deflectable relative to the driver roller.
Furthermore, the invention relates to a method for removing a surface layer including the skin from fish fillets, comprising the steps: feeding of the fish fillets lying skin side down tail end first in transport direction T by a feeding device in the region of a separating arrangement, removal of the surface layer of the fish fillets from the same by the separating arrangement, in that the fish fillets are fed lying flat between a rotationally driven driver roller and a pressing element to a main blade, the removed surface layer being dispatched downwards by way of a cutting gap S formed between the main blade and the driver roller while the fish fillet freed from the surface layer is transferred to a dispatching device, and dispatching of the fish fillets freed from the surface layer by the dispatching device.
Such apparatuses and methods are used in the fish processing industry to free fish fillets from a surface layer including the skin. In other words, said apparatus and the associated method are used to remove the layer of skin (with or without silver skin) from the fish fillets which lie skin side down on the feeding device and are transported tail end first. To do this, the feeding device and the dispatching device are arranged in the conveying (transport) plane at a distance from one another. Between the feeding device and the dispatching device, the cylindrical driver roller, which is also referred to as a skinning roller, is arranged in such a manner that the peak of the driver roller lies approximately in the conveying (transport) plane defined by the feeding device and the dispatching device. When the fish fillets arrive in the region of the driver roller, this roller pulls the fish fillets from the feeding device due to its rotational drive while the feeding device, due to its drive, continues to “push” the fish fillet. On the driver roller, the fish fillet is clamped between the driver roller and the pressing element which is usually arranged above the driver roller or it is pressed onto the textured conveying surface of the driver roller and thus transported further in the direction of the separating arrangement. The fish fillet strikes the main blade with its tail-end front face, said main blade being arranged at a distance from the driver roller to form the cutting gap S. As a result, the main blade inserts into the fish fillet between the skin and the fillet itself. The layer of skin facing downwards is dispatched downwards in the cutting gap S by the driver roller while the fish fillet freed from the skin is transported away onto the dispatching device above the main blade.
Selection of the driver roller, particularly regarding the number of teeth, and adjusting the size of the cutting gap S depend heavily on the size of the fish fillets to be processed. Different combinations of main blade and driver roller are therefore used with different sizes of fish fillet. In the known apparatuses, a large cutting gap S is required for large (and therefore also thick) fish fillets while a small cutting gap S is required for small (and therefore thin) fish fillets. There are other average cutting gap sizes between them. The size of the cutting gap S must be adjusted to the corresponding size of the fish fillet to be processed prior to processing of the fish fillets. This requires increased adjustment effort and also depends on the experience of the operator. Furthermore, for skinning larger/thicker fish fillets, a driver roller with a lower number of teeth is used, in particular to facilitate insertion of the tail end into the cutting gap S, while a driver roller with a higher number of teeth is used for skinning smaller/thinner fish fillets. This requires additional conversion effort which results in downtimes and therefore loss of production. In addition, with said apparatus and a chosen combination of main blade and driver roller, it is also only possible to achieve optimum cutting results for a certain size range of fish fillets which makes pre-sorting of the fish fillets necessary.